In the middle of the Indian Ocean, in the midst of a life-and-death struggle with nature, a nameless mariner notices a grenadine sunset and manages a faint smile. His sailing yacht disabled by bad luck and God's fury, it appears All Is Lost but not in that moment.

He is billed simply as "Our Man" in writer-director J.C. Chandor's existential adventure, and remarkably expressed by Robert Redford, weathered and nearly wordless. From the moment Our Man awakens to discover he's stranded at sea, to its Rorschach conclusion — what do you see, and what does that say about you? — All Is Lost is both practical and spiritual, now and Zen.

Chandor and Redford make an illuminating procedural of Our Man's response to calamity, calculating options, addressing essentials like patching the hull with fiberglass, whittling a bilge pump handle and desalinating water to sip. There are also acts of normalcy; prepping a meal besides canned beans, chugging two fingers of scotch, shaving before a storm. Our Man is everyman, revealed by beautifully filmed and edited action without exposition.

Not that he's a perfect hero. Redford at his youthful peak excelled at choosing roles playing against his golden boy looks. Our Man is aged yet similarly tarnished. We can surmise as much from the farewell letter of apology Redford reads in a prologue voiceover, that we'll later watch him write. He wanted to be true, kind and strong but wasn't, to whomever. Maybe Virginia Jean, his boat's namesake. Now his amends float in a pickle jar.

Chandor's screenplay — reportedly only 33 pages long — is rich with minor details coalescing into broader meaning, even allegory. The villain of the piece is a hull-gashing container that fell off a cargo ship, like the ones that later dwarf Our Man's predicament and won't notice him. The container held children's shoes, perhaps stitched by children in sweat shops overseas. Our Man is both sunk and unsaved by commercialism, in a symbolic fashion.

There are nits to be picked by sea survival experts; the most glaring is the apparent absence of life jackets on the Virginia Jean. But that's like griping about Sandra Bullock's hair not floating in the zero-g world of Gravity, a movie that All Is Lost echoes with its theme of resourceful resilience in extreme circumstances.

"I fought to the end," Our Man writes to whomever. "I don't know what that was worth." And in its quietly profound way, All Is Lost asks: Do any of us?

Steve Persall can be reached at persall@tampabay.com or (727) 893-8365. Follow @StevePersall on Twitter.